reify

re•i•fy _{verb, formal}

1. to make (something abstract) more concrete or real.
   "these instincts are, in humans, reified as verbal constructs"

Enable ECMAScript 2015 modules in Node today. No caveats. Full stop.

Usage

1. Run npm install --save reify in your package or app directory. The --save is important because reification only applies to modules in packages that explicitly depend on the reify package.
2. Call require("reify") before importing modules that contain import and export statements.

You can also easily reify the Node REPL:

% node
> require("reify/repl")
{}
> import { strictEqual } from "assert"
> strictEqual(2 + 2, 5)
AssertionError: 4 === 5
    at repl:1:1
    at REPLServer.defaultEval (repl.js:272:27)
  ...

Benefits

• Dead-simple installation and setup: npm install --save reify, require("reify")
• Works with every version of Node.
• Put import and export statements anywhere you like.
  • They're just statements.
  • If you have a philosophical preference for restricting them to the top-level, there are plenty of ways to enforce that.
  • This library doesn't limit you either way.
• Imported symbols are just normal variables.
  • Debuggers and dev tools display the symbols as you wrote them, unmangled by a transpiler.
  • Not having to rename variables references leads to much faster compilation.
  • Variables are confined to the scope where they were imported.
  • import statements work in the Node REPL.
• Any existing module or package can be imported.
  • Babel's interopRequire{Default,Wildcard} logic is captured by Module.prototype.getExportByName.
• Does not interfere with existing require.extensions hooks.
• Much simpler transform implementation as compared with other ECMASCript module compilers.
  • import statements become calls to module.import(id, setters)
  • export statements become assignments to the exports object.
  • The compiler doesn't have to parse the entire file to find import and export statements.
• Line numbers are strictly preserved.
  • No hoisting of import statements.
  • All import and export statements are compiled in-place.
• No need for Object.defineProperty-style getters to support export * from "...".
• The module.import(id, setters) API is human-writable, too, if you want to implement custom update logic.
• Generated code is statically analyzable, since the exports object is not exposed.

Drawbacks

• Only works with CommonJS module systems that are very similar to Node's module system.
• Adds some overhead to module evaluation.
• Affects every yet-to-be required module in the Node process.
• Not a general solution for other kinds of JavaScript compilation.
• Not a solution for asynchronous module loading, yet.